Double-tube superheater.



J. EGGERS.

DOUBLE TUBE SUPERHEATER.

APPLICATION FILED ocT. I2. I9Is.

meme@ Mayg, 1916.

jAr.

WITNESSES' Arron/Ins THE COLUMBIA PLANOGRAPH CD., WASHINGTON. D. c.

HEISSDAIVIPF GESELLSCHAFT, IVI. B. H. CORPORATION OF GERMANY.

, OF CASSEL-WILHELMSHHE, GERMANY, A

DOUBLE-TUBE SUPERHEATER.

Specification of Letters Patent.V

Patented May 2, 1.916.

Application filed October 12, 1915. Serial No. 55,582.

To all whom it may concern Be it known that I, JULIUs Esc-inns, a citizen of the German Empire, residing at Cassel-iVilhelmshhe, Germany, have invented certain new and useful Improvements in Double-Tube Superheaters, of which the following is a specication.

My invention relates to double tube superheaters, or superheaters in which the superheater elements proper consist of two tubes, preferably straight, inclosed one within the other in such a way that one pass of the steam is through the inner tube and the other pass through the space between the two tubes. In elements of this type the tubes are usually, but need not necessarily be, arranged concentrically. Superheater elements of this type lind their principal application in flue tube boilers.

T he object of my invention is to provide an improved construction of the sub-head ers or steam chambers into which the ends of the superheater elements open and by means of which the elements are connected together and to the `steam collectors proper or to the main steam pipes when special collectors are not used.

My invention resides substantially in constituting these connecting chambers of independent but juxtaposed boxes having their ends overlapping. These boxes are preferably arranged in rows and the outer tube of each superheater element enters the rear portion of one box while the inner tube enters the overlapping portion of the oth box. y

My invention will be better understood by referring to the accompanying drawings, in which- Figure l represents a horizontal section through one form of my invention, asintended for application to a ue tube boiler;` and Fig. E2 represents a corresponding section through a modified form of my invention, also for a flue tube boiler.

In Fig. l the superheater'element, comprising an outer tube 7c and an inner tube n has its ends fixed in hollow boxes or chambers, VB, C, which connect the saturated steam collector e and the hot or'superheated steam collectors f. These steam collectors are arranged in front of the tube sheet (not shown) the steam collector c being at the center and the collectors f laterally on each side thereof. The greater part of the right hand half of the structures of the drawing is broken away, for convenience, it being identical with the left hand half but reversed so that the two halves are symmetrical as' respects the center.

The boxes, B, C, are arranged alternately at rear and front and in a row across the front of the boiler, thus forming, looked on from above, a steam channel of undulatory shape. The forward boxes, C, are provided with rear terminal bosses having openings, E, and these bosses are entered into corren sponding bored recesses formed in the end of the rear boxes, B. A steam tight joint is insured by clamping the front and rear boxes together by means-of bolts c and clamps a.

Each rear box, B, with the exception of the box at each end of the row on each side of the boiler, has two outer tubes 7c, belonging to two independent elements, entering` and tightly fitted into the two ends thereof, while each forward box, C, has two inner tubes n, similarly entered and litted therein; in this way, by removing any forward box, two inner tubes may be simultaneously removed. The central forward box, C, is provided with a center rear opening F which is connected with the saturated steam collector c by means of an intermediate pipe section A. The end boxes, B, also have intermediate pipe connections, A, which connect them with the superheated steam collectors f.

n operation, the saturated steam passes from the central saturated steam collector, c intov the central forward box C and n thence, through the inner tubes n which enter said central box, C, at each end, and through the annular space between each tube, In, and its outer tube, 7c, into each adjacent box, B; thence through the annular space between the tube, a, and its outer tube, 7u, at the opposite end of each of these boxes, B, and so on to the terminal steam collectors 7.

In the modification represented in Fig. 2, the arrangement shown is much the same as that of Fig. l, except that the individual boxes, d, are all alike, being bent instead of straight, so as to alternately have one end in the rear and one end in front. In this way each outer tube, 7c, enters the rear end of a box while its inner tube, n., enters the rear wall of the front end of the next adjacentbox. Each front end is provided with a rear boss having an opening, E, said box being entered steam tight into a suitably bored recess in the front wall of the rear end of the adjacent box.

The central box, M, which connects with the saturated steam collector, e, and the terminal boxes, L, which connect with the superheated steam collectors, f, are straight.

The boxes, J and L, are provided with rethe adjacent box.

My invention provides an arrangement which is extremely simple in manufacture, assembly and disassembly. The number of different kinds or types of parts being few lessens the investment required to keep a suitable stock on hand for repairs and replacements. The parts are, furthermore, all exceedingly simple in form and easy of manufacture.

An important advantage of my invention is its ready' and co-mplete accessibility, not only for repairs but also for cleaning. As already stated (referring to Fig. l) the removal of any front box also withdraws the two inner tubes iixed in its end. This leaves the corresponding outer tubes, 7c, which are held by the rear box, completely open for thorough cleaning in any usual way. TheA removal of the front box merely requires the loosening of two bolts, o, and the turning of the two clamps, u, thus freed, out of the line of the boxes.

In the case of the modification shown in Fig. 2 the arrangement is perhaps, not quite so convenient, as the central box M must be removed before any of the other boxes can be removed and these other boxes must be removed successively, working from said central box. But with the removal of each box an outertube 7s is open for inspection and cleaning, while the inner tube n and the box itself, being'now away from the boiler, are also easily cleaned. The bolts and clamps, in this modification, are removed in Vsubstantially the same manner as are those of the structure of Fig.V l.

In case of total replacement of box or Copies of this patent may be obtained for tubes in either modilication it is clear that this may be quickly and easily accomplished and that the parts are simple and relatively inexpensive.

elements connecting said adjacent ends the outer tube of each element opening through the rear wall of the rear end and the inner tube passing through said rear end and opening through the rear wall of the front end, and means for detachably maintaining said boxes in fixed position relatively7 to one another.

2. In a superheater provided with main saturated and superheated steam collectors, in combination, a plurality of lineally disposed independent hollow boxes, the terminal boxes having steam connection with said main collectors respectively and the adjacent ends of neighboring boxes being held together, one in front of the other, and double tube superheater elements connecting said adjacent ends the outer tube of each element opening through the rear wall of the rear end and the inner tube passing through said rear end and opening through the rear wall of the front end.

3. In a superheater provided with main saturated and superheated steam collectors, in combination, a plurality of lineally disposed independent hollow boxes, the terminal boxes having steam connection with said main collectors respectively and cach intermediate box having its two ends respectively held against the front and against the rear of ends of two neighboring boxes, and double tube superheater elements connecting said overlapped ends the outer tube of one element opening through the rear wall of the rear end and the inner tube of another element opening through the rear wall of the front end of the same box.

In testimony whereof I have hereunto set my hand.

JULIUS EGGERS.

lfive cents each, by addressing the Commissioner of Patents,

Washington, D. C. 

